Flexible electric heater.



I. I. AYERI FLEXIBLE ELECTRIC HEATER.

APPLICATION man Auw/4.1913.

Patented July 25, 1916.

fain/e `UNITED sTATEs PATENT oEEIoE.

JAMES I. AYER, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOB TO SIMPLEX ELECTRIC HEATING COMPANY, OF CAMBRIDGE, MASSACHUSETTS, A CORPORATION OF MASSA- CHUSETTS.

FLEXIBLE ELECTRIC HEATER.

Specification of Letters Patent.

' Patented July 2,5, 1916.

Application led August 14, 1913. Serial No. 784,731.

To all lwhom t may concern Be it known that I, JAMES I. AYER, a citizen of the United States, and resident of Cambridge, county of Middlesex, State of Massachusetts, have invented an Improvement in Flexible Electric Heaters, of which the following descri tion, in connection with the accompanying rawings, is al specification, like letters on the drawings representing like parts. l

This invention relates to electric heating apparatus, and more particularly to a flexible and portable electric heater, having a protecting armor thereon, and capable of use as a footwarmer or the like. I form such heater of any suitable electrical heating element, preferably as a spirally wound electrical resistance upon a core of asbestos or the like, and cover the same with fire-proofing material, applying to such fire-proofing material a flexible protecting armor. This flexible covering may be in the form of a metallic ribbon, Wound spirally about the heating element incased in its fireroofing material, or may bein the form o a Wire or flexible tubing, so lng as sullicient protection is secured and the flexibility of such covering and of the heater as an entirety is maintained. This metallic protection pre- .vents injury to the heater when used as a foot warmer, and enables it to bear any weight which is apt to be placed upon it in use. Having provided the heating element with its metallic protecting covering as above explained, I then take a suitable length o f the heater to provide sufficient heat radiation as may be needed,'form the same in a coil or other shape, and cover the coil so formed with carpet, canvas, or any suitable fabric, so that it presents an attractive appearance as a rug or mat. The heater so formed, being flexible, portable, and with its metallic protecting covering to prevent injury to the electrical resistance, and its textile covering for appearance, finish, and wear, may be advantageously employed in a variety ofuses, such as a foot warmer 11nder a desk, adjacent an arm chair, in an automobile or 4in the sick-room, being connected to any suitable source of electrical current supply. v

Other features of the invention, novel combinationsl of parts, and details ofconstruction will be hereinafter more fully pointed out and claimed.

Referring to the drawings, illustrating a preferred embodiment ofthe invention, Figure illustrates an embodiment of the inv ention in a preferred form, having a portion of the textile covering broken away; F 1g. 2 is a view of another form of mat,

wherein the heating coil isflaid in reflexform; Fig. 3 is a fragmentary cross sectional View of my flexible electric heater; Fig. 4 is a view illustrating one form of the metallic protecting armor; and Fig.` 5 is a view illustrating the electrical heating element as formed upon avcore and embedded in the fire proofing material.

While I havel illustrated herein two forms of mats or rugs, one showing the electric heating element in the form of a flat coil, and the other in a relatively long and narrow form with the heater coiled in reflex manner, I- wish it understood that I am not limited in anyway to these two forms, as the invention, broadly considered, comprises any. flexible electric heater, having some protecting material, preferably metallic, to prevent injury to the heating element, and the entire heating coils being covered or inclosed within. a suitable finishing material, prefer-v ably fabric.`

As illustrated in the accompanying drawings, I apply to a suitable core l of asbestos or other equivalent lire proof or insulating material, an electrical resistance inI spiral form to provide the heating element, as indicated at 2, and then cover this electrical f heating element with a covering of asbestos 3, again covering the asbestos with a metallic armor, such as the metal ribbon 4, wound in a spiral manner upon the covered core so lprepared.y Instead of the flat metallic ribbon 4 I may employ a spirally Wound wirel or a flexible metal tubin to provide protection and retain the flexi ility of theheater.` /By` means of the spiral formation around a core of suitable diameter, as well as the spirally Wound armored covering, I am enabled to provide any length of such flexible electric heater, as indicated at 5, Figs. l and 2, as may be desired, to be made up into a rug or mat of any size orl form to produce any desired extent of heat radiation. As shown in Figml, I coil a suitable length of the flexible electric heater formed preferably as above explained into a round, .Y

flat matl of 'desired diameter, and cover the same with fabric 6, andl -7, uniting the various adjacent coils 5 to the fabric 6 by wire loops 8, or other suitable means. As illustrated 1n Fig. 3, I preferably alternate the wire loops 8 from one coil to the top fabric 6, and then about an adjacent coil to the lower fabric 7 and so on alternately, thus uniting both fabric surfaces 6 and 7, and retaining the mat in proper shape. At the meeting edges of the fabric 6 and 7, fastening devices 9 may be utilized or a line of stitching may be employed. Any other suitable means of holding the coils of the flexible heater 5 in proper shape may be employed, the usual buttons and stay cords, as used in upholstery being feasible.

In Fig. 2 I have illustrated a length of mat or rug with but comparatively little vheat radiation, the successive coils of lexible heater 5 being spaced apart somewhat, to reduce the heat power for a given area of mat. In this form, if the adjacent coils of the flexible heater are spaced a substantial distance apart, it may be desirable to ll in between the same with additional fabric or filling, in order to present a smooth exterior tothe textile fabric, carpet, or the like covering the same.

In both forms ofA mats illustrated in Figs. 4

1 and 2,1 arrange the terminals 10 and 11 round core with the heatingelement wound spiral form thereon, and with the fire proofing material and the metallic protecting covering also'in round form, constituting the circular flexible heater 5, it isv of course within the scope of the invention to make the' heater of any form desired, such as rectangular, elliptical, or otherwise in cross section.

An important characteristic of my pres ment arranged for the heating element at adjacent points' ent invention is that a flexible electrical heater is provided with suitable iexible armor, so that it can be wound or coiled into any shape or form, -de nding upon the uses to which it is put. y having the electrical heating element upon a core of suitable diameter, ilexibility is attained without danger of inju to the heatin element, and the form in which such a ilexi le heatermay be made up for use varies` with the purposes to which such a heater is to be put, and therefore almost any shape or form of mat, rug, or heating device can be made therefrom. The heater so made is of course portable from place to place, and from one source of current suppl to another, the flexibility of the entire eater adapting it for use in man leaces where other heatmg apparatus wo d ineffective.

Having described my invention, what I claimas new and. desire to secure by Letters Patent is:

As an article of manufacture, an electricallyT heated rug, foot-warmer, or the like, comprising a ilexible electrical heating eleas a flat but coiled form, an outer textile covering of suitable formand size for a rug, foot-warmer, or the like, and adapted to inclose the electrical heatin coils, a iireproofing substance between said electric heating element and said outer tex- 7 tile covering, a flexible protecting armor for the electrical heating element, and means to hold the coils of the electrical heater and the outer textile covering in desired shape and form.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

JAMES I. AYER.

Witnesses:

ELIZABETH M. CoNLrN, DORA A. Pnoc'ron. 

